Container closure



p 1959 M. NAPHTAL ETAL 2,904,204

CONTAINER CLOSURE Filed Aug. 14, 1956 AGE/V72 United States Patent2,904,204 CONTAINER CLOSURE Max Naphtal and Naphtal, LosAngeles, Calif.Application August 14, 1956, Serial No. 603,939

I Claims. (Cl. 215- 41) This invention relates to closures forcontainers such as bottles,'and relates particularly to a plasticreplacement for the well-known crown cap.

As is Well known, carbonated beverages such as carbonated soft drinks,carbonated malt beverages such as beer and ale, and the like arecommonly sold in narrow-necked bottles which arecapped by a so-calledcrown cap, consisting of a disk of metal so shaped as to have acorrugated side which is crimped'around the rim or head of the neck ofthe bottle, a hermetic seal being provided by a cork, paper or chipboardinsert bearing against the top of the bottle and contained within thedisk of the metal.

In'spite of the wide usage of the crown cap, it has a number ofdisadvantages. In the first place, it cannot be reused, as for examplemight be desired when only part of the contents of a bottle is used andit is desired to maintain carbonation in the remainder, because the actof removing the cap generally deforms the metal so that it no longer canbe sealed back on the bottle without the use of special apparatus notavailable to the general public. In the second place, the crown cap isnot completely sanitary, since the corrugations previously described aremerely crimped around the bead of the neck and allow more or less freeaccess of fluids and other contaminants to the edge of the sealing diskin the top of the cap, commonly known as the liner. Such contaminationmay take place when the bottle. of carbonated beverage'is cooled in theordinary soda pop cooler wherein the bottles are immersed partially orcompletely in chilled water. The chilling water is seldom changed withsufficient frequency, and is a source of bacterial contamination.'Furthermore, upon long standing in such an environmenn the cap tendsto-rust, and frequently when a bottle of carbonated beverage is opened,a deposit of rust is foundaround the outside of the bottle neck.Anothendisadvantage of the common crown cap is that it has noself-sealing property, the hermetic seal depending entirely" uponcompression of the liner, suchcomp-ression being retained by thecrimping of the corrugation around the head of the. neck. Should theliner lose resiliency during storage then the seal may be imperfect andthe carbon dioxide may escape from the beverage leading toeventual-spoilage. 3

It is. an object of the present invention to provide a wholly sanitaryclosure for bottles of the type described.

Another object of the invention is to 'provide a closure which isentirely in one piece.

J Another object of the invention is vtoprovide a closure having .selfsealing properties against internal pressure caused by the carbonationof the carbonated beverage with which it is used.

Another object of the present invention is to provide a bottle closurenot susceptible to rusting.

Another object of the present invention is to provide a bottle closurefor bottles of the type described which can be reused without loss ofsealing eflectiveness.

Another object of the invention is to provide a plastic 2 bottle capembodying unique self-sealing mechanisms so as to insure a long-lasting,perfect seal.

Other objects of the invention will become apparent as the descriptionthereof proceeds.

In the drawing, Fig.l is a side view, partly in section, showing ournovel closure in place on a bottle.

Fig. 2 is a top view of the closure of Fig. 1.

Fig. 3 is a side view in section of another embodiment of our invention.

Fig. 4 is a bottom View of the closure shown in Fig. 3.

Fig. 5 is a side view in section of another embodiment of our invention.

Fig. 6 is a top view of the closure shown in Fig. 5.

In general, in accordance with our invention, we provide a one piecemolded plastic closure, which is characterized, first, by having a thincylindrical tube-like member extending downwardly just inside the neckof the bottle. The cylindrical portion is made sufficiently thin so thatit is relatively flexible, and as will be discussed in greater detailhereinbelow, the closure is made of a plastic material having thecharacteristic of flexibility in thin sections, namely, polyethylene orapolyethylene-like substance. By the same token this material in thicksection is relatively inflexible. The cylindrical portion or tube justreferred to is prevented from being dislodged from the neck of thebottle by an annular portion which extends outwardly and downwardlyabout the head of the bottle, and this annular portion has itself aninner head which engages the head of the bottle. These features mayconveniently be seen by reference to Fig. 1, in which 10 is thecylindrical portion just inside the neck of the bottle 11, and theannular portion 12 of the closure bears an inner bead 13 which engagesthe bead 14 of the bottle. The closure is-completed by a relativelythick portion 15 which closes off the cylindrical portion 10 but isseparate therefrom although connected thereto by a relatively thin andrelatively flexible septum 16. The central portion 15 of the closure ismade relatively thick so as to be relatively inflexible, and may bedescribed generally as a disc. In the enclosure shown in Fig. 1, thelower side of the disc 15 has a conical shape, serving to strengthen thedisc 15 still further against flexing.

The operation of the closure made in accordance With our invention maybe understood by the following explanation: Gas pressure inside thebottle 11 tends to expand the cylindrical portion 10 of the closure, sothat it presses against the inside of the neck of the bottle. Thisaction is aided by the fact that the cylindrical portion 10 is flexible;and it will be readily appreciated that tangential flexibility is theproperty coming into play here. There is also naturally a tendency forthe gas pressure inside the bottle to push the cylindrical portion 10ofl, but this is prevented by the annular portion 12 which is restrainedfrom upward movement by the engagement of inner head 13 on the bead 14of the bottle. The gas pressure inside the bottle also tends to pushupward on the disc portion 15 of the closure. If this were maderelatively flexible, it wouldbow upwardly in a generally dome-shapedconfiguration and'therebypull the cylindrical portion 10 of the closureout from contact with the inside of the bottle neck. This we avoid byproviding the central portion of the closure in relatively thick,relatively inflexible form, and further by attaching it to the rest ofthe closure, and in fact to the top of the cylindrical portion thereof,by a relatively thin, relatively flexible membrane or septum 16. V

In the closure of Fig. l, we have reinforced the strength of the innerhead 13 by an outer head 14, opposite to the inner head 13 andcontiguous therewith.

In Fig. 3 there is shown a somewhat diiferent embodiment of ourinvention. In this particular embodiment, the disc shaped portion 17 ofthe closure is relatively plane in cross section; we have dispensed withthe conical lower portion of the disc as shown in Fig. 1. This issomewhat less economical ofplastic material, but on the other handresults insomewhat of a simplification in mold construction. Thecylindrical portion 18 of the closure shown inFig. 3 haslongitudinalribs 19 molded on the inside wall thereof. It will be readilyappreciated that these ribs do not affect the tangential flexibility ofthe cylindrical portion 18 of theclosure. These ribs serve to preventany collapse of the cylindrical portion of the closure when it is beingcapped on to a bottle. The closure has as before a relatively thin,relatively flexible septum 16, and an inner bead 13 and an outer bead14.

In the embodiment shown in Fig. 5, we have moved the central discupwardly so that it projects in part above the level of the remainder ofthe closure. In the closure shown in Fig. 5, we have provided the discshaped portion 20 with a dome-shaped top 21'. It will be apparent thatthe disc 20 is still connected to the cylindrical portion of the closureby a relatively thin, relatively flexible septum 16.

We construct our improved closure from polyethylene or a plastic havingthe properties of polyethylene. Polyethylene retains about the samedegree of resiliency over a wide range of temperature, is completelynon-porous and therefore is not subject to contamination, tends to bewater-repellent, and thereby aids in sealing by causing a high liquidcontact angle, and is readily obtainable commercially in molded form.However, it is to be understood that other chemical polymers havingthese same characteristics of polyethylene, viz., resilience,nonporosity, and moldability, may also be used, such as polypropylene.An additional particular advantage of polyethylene is that noplasticizer is used in commercial moldable polyethylene so that itcontains no compounds which can leach out and impart a taste to liquidsin the container. A type of polyethylene which we particularly prefer isthe so-called low-pressure polyethylene, such as is made under the tradename Marlex and others, and is described on pages 1152-1164 ofIndustrial and Engineering Chemistry for July 1956. Likewiseparticularly suitable is Ziegler process polyethylene (see BelgianPatent No. 533,362), available under the trade name of Super Dylan.These newer types of polyethylene retain substantial strength attemperatures of 250 F. or more, which makes them especially suitable incase the closures are intended for use with liquids to be pasteurized,such as for example beer.

It will be seen that the invention accomplishes its objects. A closurehas been provided which is sanitary, of one-piece construction, whichforms an excellent selfmaintaining pressure seal by virtue of itsengineered construction, and is reusable indefinitely. It will beobserved that the invention is a broad one, and that numerous changesmay be made and equivalent materials may be used in carrying out theinvention, all within the scope of the disclosure and the appendedclaims.

Having described the invention, we claim:

1. A closure of a material having the properties of polyethylene for abottle having a beaded rim, comprising a relatively thin, relativelyflexible cylindrical portion, open at the bottom, joined at the top onthe outer side thereof by an annular portion extending generallyoutwardly and downwardly and having an inner head to engage the bead ofthe bottle, and closed at the top by a relatively thick, relativelyinflexible disc of smaller diameter than the inside diameter of saidcylindrical portion, disposed coaxially with said cylindrical portion a4 and connected to said top of said cylindrical portion by a relativelythin, relatively flexible septum.

2. A closure of a material having the properties of polyethylene for abottle having a beaded rim, comprising a relatively thin, relativelyflexible cylindrical portion, open at the bottom, joined at the top onthe outer side thereof by an annular portion extending generallyoutwardly and downwardly and having an inner bead to engage the bead ofthe bottle, and having an outer bead opposite to and joined to saidinner bead, and closed at the top by a relatively thick, relativelyinflexible disc of smaller diameter than the inside diameter of saidcylindrical portion, disposed coaxially with said cylindrical" portionand connected to said top of said cylindrical portion by a relativelythin, relatively flexible septum.

3. A closure of a material having the properties of polyethylene for abottle having a beaded rim, comprising a relatively thin, tangentiallyrelatively flexible cylindrical portion, open at the bottom, joined atthe top on the outer side thereof by an annular portion extending gen-,erally outwardly and downwardly and having an inner bead to engage thebead of the bottle, and closed at the top by a relatively thick,relatively inflexible disc of smaller diameterthan the inside diameterof said cylindrical portion, disposed coaxially with said cylindricalportion and connected to said top of said cylindrical portion by arelatively thin, relatively flexible septum, the said cylindricalportion bearing a plurality of longitudinal ribs on its inner side.

4. A closure of a material having the properties of polyethylene for abottle having a beaded rim, comprising a relatively thin, relativelyflexible cylindrical portion, open at the bottom, joined at the top onthe outer side thereof by an annular portion extending generallyoutwardly and downwardly and having an inner bead to engage the head ofthe bottle, and closed at the top by a relatively thick, relativelyinflexible disc of smaller diameter than the inside diameter of saidcylindrical portion, disposed coaxially with said cylindrical portionand connected to said top of said cylindrical portion by a relativelythin, relatively flexible septum, said disc bearing a downwardlyextending conical concentric boss.

5. A closure of a material having the properties of polyethylene for abottle having a beaded rim, comprising a relatively thin, tangentiallyrelatively flexible cylindrical portion, open at the bottom, joined atthe top on the outer side thereof by an annular portion extendinggenerally outwardly and downwardly and having an inner bead to engagethe bead of the bottle, and having an outer bead opposite to and joinedto said inner bead, and closed at the top by a relatively thick,relatively inflexible disc of smaller diameter than the inside diameterof said cylindrical portion, disposed coaxially with said cylindricalportion and connected to said top of said cylindrical portion by arelatively thin, relatively flexible septum, said disc bearing adownwardly extending c0nical concentric boss.

References Cited in the file of this patent UNITED STATES PATENTS2,038,858 Sacks Apr. 28, 1936 2,772,802 Woydatt et al Dec. 4, 1956FOREIGN PATENTS 532,130 Great Britain Ian. 17, 1941 910,037 France Ian.14, 1946 62.450 France Jan. 19 1955

